Artificial lift systems, such as Electrical Submersible Pump (ESP) systems, are often used in hydrocarbon producing wells to pump fluids from the well up to the surface. A conventional ESP system typically includes a centrifugal pump that is driven by a three-phase voltage supply and a variable speed drive, both located at the surface, that deliver the three-phase power to the downhole motor via a three-phase power cable. In addition, data signals between the surface and downhole sensors are also transmitted over the power cable. Such signals include various data related to performance of downhole components and downhole measurements.
An issue arises, however, when one or more of the phases are grounded along the power cable. When this occurs, data transmission is not reliable or not possible over the power cable depending on the location at which the cable is grounded.
Accordingly, there is a need in the art for a ground fault immune power and data delivery system for use in a downhole environment.